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The work of the authors during the last years on ferroelectric thin and ultra-thin films deposited by Chemical Solution Deposition (CSD) onto silicon based substrates is reviewed in this paper. Ferroelectric layers integrated with silicon substrates have potential use in the new micro/nanoelectronic devices. Two hot issues are here considered: 1) the use of low processing temperatures of the ferroelectric film, with the objective of not producing any damage on the different elements of the device heterostructure, and 2) the downscaling of the ferroelectric material with the aim of achieving the high densities of integration required in the next generation of nanoelectronic devices. The UV-assisted Rapid Thermal Processing has successfully been used in our laboratory for the fabrication of ferroelectric films at low temperatures. Preliminary results on the CSD preparation of nanosized ferroelectric structures are shown.Este artículo revisa el trabajo realizado por los autores durante los últimos años sobre lámina delgada y ultra-delgada ferroeléctrica preparada mediante el depósito químico de disoluciones (CSD) sobre substratos de silicio. Las películas ferroeléctricas integradas con silicio tienen potenciales usos en los nuevos dispositivos micro/nanoelectrónicos. Dos aspectos claves son aquí considerados: 1) el uso de bajas temperaturas de procesado de la lámina ferroeléctrica, con el fin de no dañar los diferentes elementos que forman la heteroestructura del dispositivo y 2) la disminución de tamaño del material ferroeléctrico con el fin de conseguir las altas densidades de integración requeridas en la próxima generación de dispositivos nanoelectróncos. Los procesos térmicos rápidos asistidos con irradiación UV se están usando en nuestro laboratorio para conseguir la fabricación del material ferroeléctrico a temperaturas bajas compatibles con la tecnología del silicio. Se muestran resultados preliminares sobre estructuras ferroeléctricas nanométricas preparadas por CSD.

The temperature dependence of the ε33 T dielectric permittivity and losses of piezoelectric Mn doped 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 ceramics has been measured up to 350oC at frequencies between 1 and 100 kHz by impedance spectroscopy. The temperature dependence of the low frequency Young´s modulus and mechanical losses of the ceramics has been measured in the same temperature range by dynamic mechanical analysis in three points bending configuration. Complex ε33 T, s11 E compliance and d31 piezoelectric coefficients have been obtained from radial piezoelectric resonances at temperatures up to 90oC (before depolarisation) by an automatic iterative method. All the measurements reflect the occurrence of the ferroelectric rhombohedral to ferroelectric tetragonal phase transition, which is thougth to be responsible of the high electromechanical response of the PMN-PT system, and allow describing some of its characteristics for the investigated ceramics.Se ha medido por espectroscopía de impedancias la dependencia con la temperatura hasta 350oC de la permitividad y las pérdidas dieléctricas, ε33 T y tan δ, de cerámicas piezoeléctricas de 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 dopadas con Mn a frecuencias entre 1 y 100 kHz. Se ha medido por análisis mecánico dinámico en la configuración de flexión por tres puntos la dependencia con la temperatura en el mismo rango del módulo de Young y las pérdidas mecánicas de baja frecuencia de las cerámicas. Se han obtenido por un método automático iterativo los coeficientes del material ε33 T, módulo elástico s11 E y coeficiente piezoeléctrico d31 en forma compleja a partir de resonancias radiales piezoeléctricas a temperaturas entre ambiente y 90oC (antes de la despolarización). Todas las medidas reflejan la existencia de la transición de la fase ferroeléctrica con estructura romboédrica a la fase ferroeléctrica con estructura tetragonal, que se cree responsable de la alta respuesta electromecánica del sistema PMN-PT, y permiten describir algunas de sus caracterísiticas para las cerámicas concretas investigadas.

The environmental protection issues are driving forces nowadays in the scientific research on materials. From this point of view, it is a need to find alternatives to the present commercial piezoceramics, based on lead titanates-zirconates. The production of these materials requires handling of big amounts of lead oxide, which is highly toxic. Alkaline niobate piezoceramics are considered a good alternative for the future substitution of commercial piezoceramics by lead-free materials. However, the processing of these ceramics is difficult by conventional ceramic routes. There is a need to search for new routes of processing. The mechanochemical activation was used in this work for the first time to get Na1-xLixNbO3 ceramics in the Na rich region. Stoichiometric mixtures of Na2CO3 or Na2O, Li2CO3 and Nb2O5 were activated in a vibrating mill. A progressive broadening of the X-ray diffraction peaks of the mixtures was observed as the milling time increased. Nevertheless, the precursors did not became fully amorphous. The thermal evolution of the activated precursors was also tested. Ceramics were obtained by sintering or hot pressing and their piezoelectric properties were studied.La protección medioambiental es uno de los factores que impulsan diversas áreas de la investigación en materiales. Existe la necesidad de la búsqueda de alternativas a las cerámicas ferro-piezoeléctricas comerciales basadas en los titanatos-circonatos de plomo, que requieren el manejo de grandes cantidades de óxido de plomo, muy tóxico, en su procesado. Los niobatos alcalinos se consideran buenos candidatos para esta sustitución. Sin embargo, es difícil conseguir cerámicas con altas densificaciones. De aquí la necesidad de investigar nuevas rutas de procesado. La activación mecanoquímica se ha utilizado por primera vez en este trabajo para obtener cerámicas de Na1-xLixNbO3, en la región rica en Na. Se han activado mecanoquímicamente mezclas estequiométricas de Na2CO3 o Na2O, Li2CO3 y Nb2O5 en un molino vibratorio. Se ha observado el progresivo ensanchamiento de los picos de difracción de rayos X de las mezclas a medida que se aumentaba el tiempo de molienda, pero los precursores no llegan a ser amorfos para la difracción de rayos X. A partir de estos precursores se han obtenido cerámicas mediante sinterización o prensado en caliente y estudiado sus propiedades piezoeléctricas.

A pyrochlore to perovskite transformation is known to occur during the rapid heating of sol-gel prepared La modified lead titanate ferroelectric thin films. This transformation is not inhibited by the Pb deficiency caused by PbO volatilisation at the initial stages of the thermal treatment. The microstructural evolution associated with this transformation occurring in the Pb deficient film has been studied by transmission electron microscopy. Plan view and cross section specimens were prepared from two films at different stages of the transformation. Experiments showed that the pyrochlore phase was homogenously distributed across the film thickness, with a very similar morphology to that of the ferroelectric phase. The combination of microdiffraction and microanalysis allowed identifying single grains that had not the perovskite structure, and were more Pb deficient than the film. Pore growth, grain growth, and growth of local texturing were observed along with the transformation.Es conocido que se produce una transformación de estructura pirocloro a perovskita durante el calentamiento rápido de láminas delgadas ferroeléctricas de titanato de plomo modificadas con La, preparadas por sol-gel. La deficiencia de Pb causada por la volatilización de PbO en los primeros momentos del tratamiento térmico no inhibe la transformación. Se ha estudiado, por microscopía electrónica de transmisión, la evolución microestructural asociada a esta transformación, que ocurre en un medio que en promedio es deficiente en Pb. Con este fin, se prepararon muestras para microscopía, tanto del plano de la lámina como secciones transversales, a partir de dos láminas en las que la transformación se encontraba en estadios diferentes. Los experimentos pusieron de manifiesto que la fase con estructura pirocloro se encontraba homogéneamente distribuida a lo largo del espesor de la lámina, y que su morfología era muy similar a la de la fase ferroeléctrica. La combinación de las técnicas de microdifracción y microanálisis permitió identificar granos individuales que no tenían la estructura perovskita, y establecer que presentaban una deficiencia de Pb mayor que el promedio de la lámina. La microscopía electrónica de transmisión también puso de manifiesto fenómenos de crecimiento de poro, de grano, y del grado de texturación local durante la transformación.

Ceramics of composition (SrBi2Nb2O9)1-x(Bi3TiNbO9)x with x = 0.35, 0.65 and 1.00 and Aurivillius type structure have been prepared by natural sintering and hot pressing. Amorphous precursors were obtained by mechanochemical activation of stoichiometric mixtures of oxides and carbonates, which allows using moderate processing temperatures. These materials are interesting for their use as high temperature piezoelectrics. Dielectric characterisation allows to know the temperature at what takes place the ferro-paraelectric transition, which limits the working temperature of the material. It also gives information on how the electric properties, especially the d. c. conductivity, affect the polarizability of the ceramics. The properties relation with the microstructure and the texture is studied. In this work, dielectric studies of these materials have been made, in the frequency interval from 100 Hz to 5 MHz and in the temperature range from 200 ºC up to the ferroparaelectric transition temperatures (>900 ºC for Bi3TiNbO9).Se han preparado cerámicas de la solución sólida (SrBi2Nb2O9)1-x(Bi3TiNbO9)x con x = 0.35, 0.65 y 1.00 y estructura tipo Aurivillius obtenidas por sinterización natural y por prensado en caliente. Se parte de precursores amorfos obtenidos por activación mecanoquímica de una mezcla estequiométrica de óxidos y carbonatos, lo que permite utilizar temperaturas moderadas de procesado. Estos materiales son interesantes por su posible uso como piezoeléctricos de alta temperatura. La caracterización dieléctrica permite establecer a qué temperatura se encuentra la transición ferro-paraeléctrica que limita la temperatura de uso del material y como afectan las propiedades eléctricas, especialmente la conductividad d. c., a la polarizabilidad de las cerámicas, así como su relación con su microestructura y textura. En este trabajo se ha realizado el estudio dieléctrico de estos materiales en el intervalo de frecuencias de 100 Hz a 5 MHz y en el rango de temperaturas desde 200 ºC hasta temperaturas por encima de la de la transición ferro-paraeléctrica de cada composición (>900 ºC para Bi3TiNbO9).

Lanthanum modified lead titanate thin films have been prepared by sol-gel onto two types of substrates: A: Ti/Pt/Ti/(100)Si, annealed at 650 ºC, and B: Pt/TiO2/(100)Si. Films with different thicknesses have been obtained by a multiple deposition and crystalisation process. X-ray diffraction study shows two kind of preferred orientations: films onto A substrate have // orientations, and films onto B substrate have /. Ferroelectric characterisation of the films have been carried out by means of hysteresis loops and switching currents measurements. Thickness and preferred orientation effects on these properties have been analysed. The highest values of remanent and switchable polarisation were Pr~35 μC/cm2 y Pc~23 μC/cm2.Se han preparado láminas de titanato de plomo modificado con lantano por una técnica sol-gel, sobre dos tipos de substratos: A: Ti/Pt/Ti/(100)Si, recocido a 650 ºC, y B: Pt/TiO2/(100)Si. Se han conseguido láminas con diferentes espesores mediante un proceso de sucesivo depósito y cristalización. El análisis por difracción de rayos X muestra dos tipos de orientación: // para las láminas sobre el substrato A, y / para las láminas sobre el substrato B. La caracterización ferroeléctrica de las láminas se ha realizado mediante el análisis de los ciclos de histéresis y las corrientes de conmutación ferroeléctrica, estudiándose el efecto del espesor y del tipo de orientación preferente sobre estas propiedades. Los valores más altos obtenidos de polarización remanente y polarización conmutable fueron respectivamente de Pr~35 μC/cm2 y Pc~23 μC/cm2.

Bi3TiNbO9 is one of the Aurivilius-type structure compounds, of general formula [Bi2O2][An-1BnO3n+1], made from pseudoperovskite (with n=2) layers alternating with Bi2O2 layers. It belongs to an ensemble of high transition temperature ferroelectrics that attracts nowadays a great deal of interest as piezoelectric materials for high temperature use (p.e. in non-destructive testing of materials by ultrasounds for siderurgy, nuclear plants or petrochemical industry). When prepared as thin films, they have interest as non-volatile computer memories (FERAM), due to their reduced fatigue, large polarization retention and low leakage currents. In solid state reaction and sintering, the lamellae-like growing habit, that resembles the layered crystalline structure, gives place to porous ceramics. Previous works used hot uniaxial pressing in order to obtain dense ceramics at low temperatures, avoiding changes in stoichiometry and exagerated grain growth. But, such ceramics have anisotropic properties. In order to overcome these problems, Bi3TiNbO9 ceramics were obtained by cold-pressing of amorphous powder and sintering. The amorphous precursor was obtained by mechanochemical activation of a stoichiometric oxides mixture. The quantitative microstructural, ferro and piezoelectric characterization of the ceramics reveals that these ceramics have lower porosity, higher hardness, are better polarizable and show higher piezoelectric response that those prepared from solid state reaction powder.El compuesto Bi3TiNbO9 presenta una estructura tipo Aurivillius, de fórmula general [Bi2O2][An-1BnO3n+1], constituida por capas de pseudo-perovskita (con n=2) intercaladas con capas de Bi2O2. Pertenece a una familia de ferroeléctricos de alta temperatura de transición, que son interesantes como materiales piezoeléctricos para usos a alta temperatura y, cuando se preparan en lámina delgada, en su aplicación en memorias ferroeléctricas no volátiles (FERAM). La sinterización convencional de muestras prensadas de polvo precursor obtenido por síntesis de estado sólido, que es de difícil compactación, da lugar a cerámicas porosas. Esto es debido a su hábito de crecimiento, asemejándose a su estructura cristalina, que da lugar a partículas con morfología laminar. En trabajos previos se ha hecho uso del prensado en caliente uniaxial, consiguiéndose cerámicas de baja porosidad, pero con propiedades anisótropas. En este trabajo se describe la obtención de cerámicas isótropas de Bi3TiNbO9, obtenidas por sinterización natural de muestras prensadas de polvo amorfo, que se ha obtenido mediante activación mecanoquímica de una mezcla estequiométrica de óxidos. La caracterización microestructural cuantitativa, ferroeléctrica y piezoeléctrica de estas cerámicas revela que son menos porosas, tienen mayor dureza, son más polarizables y presentan una mayor respuesta piezoeléctrica que las obtenidas por sinterización natural de polvo precursor sintético.

The ferroelectric properties of calcium modified lead titanate (Pb0.76Ca0.24)TiO3 (PTCa) thin films prepared by a sol - gel method with successive crystallisations on three different substrates (A) Pt / Ti / SiO2 / Si (100), (B) Ti / Pt / Ti / SiO2 / Si(100) y (C) Pt / TiO2 / SiO2 /Si (100), have been studied. The results of the ferroelectric characterisation show values of the spontaneous pyroelectric coefficient close to ≈ 5 .10-9 C cm-2 K-1. The low switching properties favour the stabilisation in time of the pyroelectric coefficient value. Alatter annealing thermal treatment (650ºC 1h) produces changes in the ferro - piezoelectric properties that can be related with changes in the texture of the films.Se han estudiado las propiedades ferroeléctricas de láminas delgadas de titanato de plomo modificado con calcio (Pb0.76Ca0.24)TiO3 (PTCa) preparadas vía sol gel mediante cristalizaciones sucesivas sobre tres tipos de substratos: (A) Pt / Ti / SiO2 / Si (100), (B) Ti / Pt / Ti / SiO2 / Si(100) y (C) Pt / TiO2 / SiO2 /Si (100). Los resultados de la caracterización ferroeléctrica muestran valores del coeficiente piroeléctrico espontáneo entorno a ≈ 5 .10-9 C cm-2 K-1. La baja conmutabilidad de las láminas facilita la estabilización del valor del coeficiente piroeléctrico en el tiempo. Un tratamiento térmico posterior de recocido a 650ºC 1 hora produce cambios en las propiedades ferro-piezoeléctricas que se pueden asociar con modificaciones de la textura en las láminas.

Lanthanum modified lead titanate ferroelectric thin films with a composition Pb0.7La0.2TiO3 have been prepared by a diol based sol-gel technique. The effect on the film structure, microstructure and composition of the initial PbO content, from the nominal value to an excess of 20 mole%, and of the heating rate of the thermal treatment of crystallisation at 650ºC, from 10ºC min-1 to more than 500ºC min-1, has been studied. It is not possible to obtain single phase films with the treatment at 10ºC min-1, even when PbO volatilisation is compensated with an initial excess of PbO of 20 mole%. It is possible with the treatment at more than 500ºC min-1 and the latter excess of PbO. These films present a relative dielectric permittivity at room temperature of ε= 700, and a variation between room temperature and 100ºC of Δε = 75, being both parameters very interesting for DRAMs.Se han preparado láminas delgadas ferroeléctricas de titanato de Pb modificado con un 20% de La, Pb0.7La0.2TiO3, por una técnica sol-gel basada en la ruta de los dioles. Se ha variado el contenido inicial de PbO, del nominal a un exceso del 20% molar; y la velocidad de calentamiento en el tratamiento térmico de cristalización a 650ºC, de 10ºC min-1 a más de 500ºC min-1, y estudiado su efecto en la microestructura, estructura y composición de las láminas. No es posible obtener láminas monofásicas con el tratamiento con 10oC min-1, aun compensando la volatilización de PbO con un exceso inicial del 20% molar. Sí lo es con tratamiento rápido manteniendo dicho exceso de PbO. Estas últimas láminas presentan una permitividad dieléctrica a temperatura ambiente de ε=700, y una variación entre ambiente y 100ºC de Δε= 75, parámetros muy interesantes para memorias DRAMs.

Nanoindentation techniques have been used to determine the mechanical properties of two well characterised Pb0.88La0.08TiO3 ferroelectric thin films which have been shown to be promising for MEMs applications. Aceramic with the same nominal composition and the substrate material were also tested as an aid in the interpretation of results. Test routines have been developed using the spherical indentation geometry to distinguish the elastic and permanent deformation of the materials. Mechanical data for different layers in the heterostructure could be determined by using indenters with different radii. The technique provides information on the elastic modulus of the film, the onset and nature of permanent deformation, film delamination and the effects of porosity and residual stress. These techniques open the possibility to characterise fully the mechanical response of a microdevice.Se han usado técnicas de nanoindentación para determinar las propiedades mecánicas de dos láminas delgadas ferroeléctricas de Pb0.88La0.08TiO3 bien caracterizadas y que se han considerado prometedoras para aplicaciones MEMs. También se han realizado medidas en una cerámica con la misma composición nominal y en el sustrato de las láminas como ayuda para la interpretación de los resultados. Se han desarrollado rutinas usando la geometría de indentación con esfera para distinguir las deformaciones elástica y permanente del material. Podría ser posible obtener parámetros mecánicos de las distintas capas de la heteroestructura lámina sustrato mediante el uso de indentadores con radio distinto. La técnica proporciona información sobre el modulo elástico de la lámina, el comienzo y la naturaleza de la deformación permanente, delaminación y el efecto de la porosidad y las tensiones residuales. Estas técnicas abren la posibilidad de caracterizar completamente la respuesta mecánica de un microdispositivo.

Ductile iron contains free graphite nodules within the metallic matrix, which generally consists of ferrite and pearlite in the as-cast condition. The casting thicknesses have a great influence on the size, shape, and quantity of the microconstituents of the metallic matrix and the graphite nodules and thus on the mechanical properties. In this study the cooling rate (caused by the casting thicknesses) on the metallic matrix and the nodular characteristics of a low alloyed ductile iron with 0.8 %Ni and 0.15 %V was investigated. The ductile iron was produced in a sandwich process with ladle inoculation. Six plates of different thicknesses, from 4.3 mm to 25.4 mm, were produced in a green sand mold. The microstructural characterization was performed by optical microscopy (OM), scanning electron microscopy (SEM), and the image J software using different quantification methods. The area method to determine the average nodule size and nodular structure provided more reliable results than the perimeter and total particle count methods. The hardness test on the Rockwell C scale was used for the mechanical characterization. The low content of vanadium added to the ductile cast iron had a negligible effect on the solidification pattern, which was mainly due to the graphitizing impact of the nickel and silicon addition. The results of the microstructural characteristics are therefore primarily due to the cooling rate, which is determined by the casting thickness. The thinnest casting section significantly improved the number of nodules (414 Nod/mm2), sphericity (0.96), and nodularity (96.21 %). In contrast, the thickest casting plate obtained the highest volume fraction of graphite (10.85 %) and the lowest volume fraction of unwanted particles (0.36 %). The high cooling rate in the thinnest casting plate resulted in the highest hardness of 31.56 HRC due to the higher volume fraction of the pearlite (33.7 %) and carbides (4.5 %).

Maximiliano Diaz-Menindez,1 Dan Morgenstern-Kaplan,2 Lyda Cuervo-Pardo,3 Santiago Alvarez-Arango,4,5 Alexei Gonzalez-Estrada6 1Division of Pulmonary, Allergy, and Sleep Medicine, Department of Medicine, Mayo Clinic, Jacksonville, FL, USA; 2Department of Internal Medicine, University of Miami/Jackson Health System, Miami, FL, USA; 3Division of Rheumatology, Allergy and Clinical Immunology, Department of Medicine, University of Florida, Gainesville, FL, USA; 4Division of Clinical Pharmacology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; 5Division of Allergy and Clinical Immunology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; 6Division of Allergy, Asthma and Clinical Immunology, Department of Medicine, Mayo Clinic, Phoenix, AZ, USACorrespondence: Alexei Gonzalez-Estrada, Division of Pulmonary, Allergy and Sleep Medicine, Department of Medicine, 5777 E. Mayo Blvd, Phoenix, AZ, 85054, USA, Tel +1 480-301-4284, Fax +1 480-301-4041, Email gonzalez.alexei@mayo.eduAbstract: Hereditary angioedema (HAE) is a condition characterized by episodes of cutaneous and submucosal edema. Angioedema of the extremities and abdominal attacks are the most common manifestations of the disease. It can also affect the upper airways with the potential of becoming life-threatening. The two most common causes of HAE are a deficiency of C1 inhibitor (classified as type 1 HAE) or a dysfunction of C1 inhibitor (type 2 HAE). A malfunction or deficiency of C1 inhibitor leads to an overactivated plasma kallikrein (an inflammatory vasoactive peptide), that increases bradykinin, mediating the angioedema episodes in patients with HAE. To minimize the difficulties of this pathology and to improve patients’ quality of life, prevention of this condition is essential. Berotralstat is a unique option for oral administration for routine prophylaxis. This drug acts by binding to kallikrein and reducing its plasma activity, lowering bradykinin levels. Open-label studies have demonstrated the effectiveness of a single daily dose of berotralstat 150 mg in preventing HAE attacks. This review aims to examine studies performed to elucidate the efficacy, safety, and tolerability of berotralstat.Keywords: hereditary angioedema, berotralstat

Coastal ocean temperatures can respond to different atmospheric and oceanic processes at local spatial scales or through remote teleconnections. This study focused on subsurface ocean temperatures (subT) at 10 m depth in Maxwell Bay, northern Antarctic Peninsula from February 2017 and January 2022. It investigated extreme warming events during austral summers and their interaction with atmospheric and oceanic conditions regionally and locally. The analysis identified active and extreme Marine Heat Waves (MHWs) in March 2017 and January‐February 2020 associated with a significantly negative Southern Annular Mode index observed 3–4 months before the temperature increase. In March 2017, temperatures exceeded the climatological mean by over 1°C. This anomaly was linked to a strengthened Amundsen Sea Low and a blocking anticyclone moving between the Scotia Sea and the South‐West Atlantic Ocean that deflected westerly winds and facilitated the anomalous transport of warmer northern air masses to the AP. In January‐February 2020, the highest recorded subT was observed (2.97°C), although air‐sea heat fluxes did not show a similar pattern. In February 2020, one of the most intense atmospheric heatwaves ever recorded in West Antarctica was observed. This heatwave corresponded with maximum subT and positive sea surface temperature anomalies extending throughout the western region of the Southern Ocean, related to an extremely negative Southern Annular Mode. This study provides valuable insights into the impact of strong MHWs, a phenomenon that has been less documented in Antarctic coastal regions. Plain Language Summary: Understanding how ocean temperature varies and responds to different local and remote forcings is crucial for quantifying the potential impact of temperature fluctuations on the coastal Antarctic environment. Between 2017 and 2022 in Maxwell Bay, Antarctic Peninsula, the response of subsurface ocean temperatures (subT, temperature at 10 m depth) to extreme warming events was recorded and analyzed in relation to atmospheric and oceanic conditions. Extreme warming events in the ocean, identified as Marine Heat Waves, occurred in March 2017 and in January and February 2020. In March 2017 subT exceeded the historical averaged temperature by over 1°C. The increase in subT was associated with the deflection of the typically dominant westerly winds to the south, which transported warmer northern air to the Peninsula. In January 2020, the highest recorded subT was observed (2.97°C). Observations suggested this warming was related to the negative Southern Annular Mode in 2019. This study provides valuable insights into the environmental variability and temperature ranges that affect Antarctic marine communities. Key Points: Subsurface ocean temperature (subT, temperature at 10 m depth) in a coastal Antarctic embayment responded to extreme warming eventsSubT recorded Marine Heat Waves in summers 2017 and 2020, identified as years of extreme negative Southern Annular Mode prior to extremely high subTThe main dominant modes of subT variability were related to the Amundsen Sea Low and the Southern Annular Mode [ABSTRACT FROM AUTHOR]